Traditional mechanical slot machines include three or four reels rotatably mounted on a common axis. Each reel has different indicia spaced around its periphery. The indicia may be pictures of bells, bars, fruit, or any number of other symbols to suit a particular theme for the slot machine. Lines that are formed along a number of reel locations are referred to as “paylines.” For example, a payline may be formed parallel to the common axis. In operation, a player makes a wager concerning a given payline, and then pulls a handle on the mechanical slot machine to spin the reels. The indicia that line up along the payline when the reels stop spinning represents a result for the payline. Different sets of indicia on the payline represent different results for the player.
In some mechanical reel slot machines, a result for a given play of the game may be generated by a random result generator associated with the slot machine and each reel may be forced to stop spinning at the appropriate position to show the proper set of indicia along the payline for the result. Alternatively, the spinning reels are otherwise randomly stopped or are allowed to stop at various positions and the stop positions themselves determine the indicia that line up along a given payline to represent a result for the play. In either case, the indicia that line up along a payline when the reels stop spinning determine or indicate the result associated with the play and correlate to any prize for the result.
The vertically oriented reels in a typical mechanical slot machine are placed behind a glass plate with the indicia on the periphery of the reels facing the player position. The diameter of the reels is commonly such that three adjacent indicia on each reel face the player position so that a player in that position may see all three adjacent indicia on each reel. Where three adjacent indicia on each reel are visible to the player, the slot machine may have three horizontal paylines. Other three reel slot machines have three horizontal paylines, three vertical paylines, and two diagonal paylines for a total of eight different paylines. Yet other slot machines may define angled paylines through the various indicia positions visible to the player facing the gaming machine.
Mechanical reel-type gaming machines present a number of problems. For example, a mechanical reel-type gaming machine is prone to break down due to the mechanical nature of the device. In addition, mechanical reel-type machines do not offer an easy way to change the appearance of the gaming machine. For these reasons, manufacturers of mechanical reel-type gaming machines have reduced the number of mechanical components in the reel-type gaming machines. In particular, many modem slot machines replace the mechanical reels with a video display that is driven to simulate spinning reels. These electronic versions of reel-type gaming machines offer flexibility in modifying reel indicia and reduce the number of mechanical components in the mechanical reel-type gaming machines. However, among other problems, prior video gaming machines that imitate mechanical reel-type gaming machines may not look realistic depending upon the quality of the video display and the graphics processing arrangement associated with the gaming machine.